Due to higher integration of semiconductor devices, scratches or defects of semiconductor wafers, caused upon lapping or chemical-mechanical double side polishing (DSP) among wafer manufacturing processes, have been recognized as an important factor having a great effect on the yield and productivity of semiconductor devices. In particular, in the case of recent processes of manufacturing semiconductor devices using large-diameter wafers (e.g., wafers having a diameter of 300 mm), wafers, lapping plates, polishing heads, polishing pads and the like are being increased in size and precision.
Slurry is used in conventional lapping or double side polishing. In the case of conventional slurry supply devices, when slurry is supplied from a nozzle (not shown) to a slurry ring (not shown), contaminants, such as dust, metal or the like, may be attached to the slurry, thereby causing the slurry to be adhered to an inner slurry pipe of an upper plate or causing contamination of or damage to an object to be polished.